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Biology subjects

Du, H.

Publications and source records attributed to Du, H..

At least 109 records · Page 6Linked to original sources

Evolution and molecular characteristics of SARS-CoV-2 genome

ObjectivesTo reveal epidemic trend and possible origins of SARS-CoV-2 by exploring its evolution and molecular characteristics based on a large number of genomes since it has infected millions of people and spread quickly all over the world. MethodsVarious evolution analysis methods were employed. ResultsThe estimated Ka/Ks ratio of SARS-CoV-2 is 1.008 or 1.094 based on 622 or 3624 SARS-CoV-2 genomes, and the time to the most recent common ancestor (tMRCA) was inferred in late September 2019. Further 9 key specific sites of highly linkage and four major haplotypes H1, H2, H3 and H4 were found. The Ka/Ks, detected population size and development trends of each major haplotype showed H3 and H4 subgroups were going through a purify evolution and almost disappeared after detection, indicating H3 and H4 might have existed for a long time, while H1 and H2 subgroups were going through a near neutral or neutral evolution and globally increased with time. Notably the frequency of H1 was generally high in Europe and correlated to death rate (r>0.37). ConclusionsIn this study, the evolution and molecular characteristics of more than 16000 genomic sequences provided a new perspective for revealing epidemiology of SARS-CoV-2.

bioinformatics↗

Deletion of the mitochondrial matrix protein cyclophilin-D prevents parvalbumin interneuron dysfunction and cognitive deficits in a mouse model of NMDA hypofunction

Redox dysregulation and oxidative stress are final common pathways in the pathophysiology of a variety of psychiatric disorders, including schizophrenia. Oxidative stress causes dysfunction of GABAergic parvalbumin-positive interneurons (PVI), which are crucial for the coordination of neuronal synchrony during sensory- and cognitive-processing. Mitochondria are the main source of reactive oxygen species (ROS) in neurons and they control synaptic activity through their roles in energy production and intracellular calcium homeostasis. We have previously shown that in male mice transient blockade of NMDA receptors during development (subcutaneous injections of 30 mg/kg ketamine (KET) on postnatal days 7, 9, and 11) results in long-lasting alterations in synaptic transmission and reduced parvalbumin expression in the adult prefrontal cortex (PFC), contributing to a behavioral phenotype that mimics multiple symptoms associated with schizophrenia. These changes correlate with oxidative stress and impaired mitochondrial function in both PVI and pyramidal cells. Here, we show that genetic deletion (Ppif-/-) of the mitochondrial matrix protein cyclophilin D (CypD) prevents perinatal KET-induced increases in ROS and the resulting deficits in PVI function, and changes in excitatory and inhibitory synaptic transmission in the PFC. Deletion of CypD also prevented KET-induced behavioral deficits in cognitive flexibility, social interaction, and novel object recognition. Taken together, these data highlight how mitochondrial activity may play an integral role in modulating PVI-mediated cognitive processes. Significance StatementMitochondria are important modulators of oxidative stress and cell function, yet how mitochondrial dysfunction affects cell activity and synaptic transmission in psychiatric illnesses is not well understood. NMDA receptor blockade with ketamine during development causes oxidative stress, dysfunction of parvalbumin-positive interneurons (PVI), and long-lasting physiological and behavioral changes. Here we show that mice deficient for the mitochondrial matrix protein cyclophilin D show robust protection from PVI dysfunction following perinatal NMDAR-blockade. Mitochondria serve as an essential node for a number of stress-induced signaling pathways and our experiments suggest that failure of mitochondrial redox regulation can contribute to PVI dysfunction.

neuroscience↗

CBRPP: a new RNA-centric method to study RNA-protein interactions

RNA-protein interactions play essential roles in tuning gene expression at RNA level and modulating the function of proteins. Abnormal RNA-protein interactions lead to cell dysfunction and human diseases. Therefore, mapping networks of RNA-protein interactions is crucial for understanding cellular mechanism and pathogenesis of diseases. Different practical protein-centric methods for studying RNA-protein interactions has been reported, but few RNA-centric methods exist. Here, we developed CRISPR-based RNA proximity proteomics (CBRPP), a new RNA-centric method to identify proteins associated with the target RNA in native cellular context without cross-linking or RNA manipulation in vitro. CBRPP is based on a fusion of dCas13 and proximity-based labeling (PBL) enzyme. dCas13 can deliver PBL enzyme to the target RNA with high specificity, while PBL enzyme labels the surrounding proteins of the target RNA, which are then identified by mass spectrometry.

molecular biology↗

Prediction and Evolution of B Cell Epitopes of Surface Protein in SARS-CoV-2

The discovery of epitopes is helpful to the development of SARS-CoV-2 vaccine. The sequences of the surface protein of SARS-CoV-2 and its proximal sequences were obtained by BLAST, the sequences of the whole genome of SARS-CoV-2 were obtained from the GenBank. Based on the NCBI Reference Sequence: NC_045512.2, the conformational and linear B cell epitopes of the surface protein were predicted separately by various prediction methods. Furthermore, the conservation of the epitopes, the adaptability and other evolutionary characteristics were also analyzed. 7 epitopes were predicted, including 5 linear epitopes and 2 conformational epitopes, one of the linear and one of the conformational were coincide. The epitope D mutated easily, but the other epitopes were very conservative and the epitope C was the most conservative. It is worth mentioning that all of the 6 dominated epitopes were absolutely conservative in nearly 1000 SARS-CoV-2 genomes, and they deserved further study. The findings would facilitate the vaccine development, had the potential to be directly applied on the treatment in this disease, but also have the potential to prevent the possible threats caused by other types of coronavirus.

bioinformatics↗

The Genomic Formation of Human Populations in East Asia

The deep population history of East Asia remains poorly understood due to a lack of ancient DNA data and sparse sampling of present-day people. We report genome-wide data from 191 individuals from Mongolia, northern China, Taiwan, the Amur River Basin and Japan dating to 6000 BCE - 1000 CE, many from contexts never previously analyzed with ancient DNA. We also report 383 present-day individuals from 46 groups mostly from the Tibetan Plateau and southern China. We document how 6000-3600 BCE people of Mongolia and the Amur River Basin were from populations that expanded over Northeast Asia, likely dispersing the ancestors of Mongolic and Tungusic languages. In a time transect of 89 Mongolians, we reveal how Yamnaya steppe pastoralist spread from the west by 3300-2900 BCE in association with the Afanasievo culture, although we also document a boy buried in an Afanasievo barrow with ancestry entirely from local Mongolian hunter-gatherers, representing a unique case of someone of entirely non-Yamnaya ancestry interred in this way. The second spread of Yamnaya-derived ancestry came via groups that harbored about a third of their ancestry from European farmers, which nearly completely displaced unmixed Yamnaya-related lineages in Mongolia in the second millennium BCE, but did not replace Afanasievo lineages in western China where Afanasievo ancestry persisted, plausibly acting as the source of the early-splitting Tocharian branch of Indo-European languages. Analyzing 20 Yellow River Basin farmers dating to [~]3000 BCE, we document a population that was a plausible vector for the spread of Sino-Tibetan languages both to the Tibetan Plateau and to the central plain where they mixed with southern agriculturalists to form the ancestors of Han Chinese. We show that the individuals in a time transect of 52 ancient Taiwan individuals spanning at least 1400 BCE to 600 CE were consistent with being nearly direct descendants of Yangtze Valley first farmers who likely spread Austronesian, Tai-Kadai and Austroasiatic languages across Southeast and South Asia and mixing with the people they encountered, contributing to a four-fold reduction of genetic differentiation during the emergence of complex societies. We finally report data from Jomon hunter-gatherers from Japan who harbored one of the earliest splitting branches of East Eurasian variation, and show an affinity among Jomon, Amur River Basin, ancient Taiwan, and Austronesian-speakers, as expected for ancestry if they all had contributions from a Late Pleistocene coastal route migration to East Asia.

genomics↗

Persistent cell proliferation signals correlates with increased glycolysis in tumor hypoxia microenvironment across cancer types

BackgroundAltered metabolism is a hallmark of cancer and glycolysis is one of the important factors promoting tumor development. Given that the absence of multi-sample big data research about glycolysis, the molecular mechanisms involved in glycolysis or the relationships between glycolysis and tumor microenvironment are not fully studied. Thus, a more comprehensive approach in a pan-cancer landscape may be needed. MethodsHere, we develop a computational pipeline to study multi-omics molecular features defining glycolysis activity and identify molecular alterations that correlate with glycolysis. We apply a 22-gene expression signature to define the glycolysis activity landscape and verify the robustness using clinically defined glycolysis samples from several previous studies. Based on gene expression signature, we classify about 5552 of 9229 tumor samples into glycolysis score-high and score-low groups across 25 cancer types from The Cancer Genome Atlas (TCGA) and demonstrate their prognostic associations. Moreover, using genomes and transcriptome data, we characterize the association of copy-number aberrations (CNAs), somatic single-nucleotide variants (SNVs) and hypoxia signature with glycolysis activity. FindingsGene set variation analysis (GSVA) score by gene set expression was verified robustly to represent glycolytic activity and highly glycolytic tumors presented a poor overall survival in some cancer types. Then, we identified various types of molecular features promoting tumor cell proliferation were associated with glycolysis activity. Our study showed that TCA cycle and respiration electron transport were active in glycolysis-high tumors, indicating glycolysis was not a symptom of impaired oxidative metabolism. The glycolytic score significantly correlated with hypoxia score across all cancer types. Glycolysis score was also associated with elevated genomic instability. In all tumor types, high glycolysis tumors exhibited characteristic driver genes altered by CNAs identified multiple oncogenes and tumor suppressors. We observed widespread glycolysis-associated dysregulation of mRNA across cancers and screened out HSPA8 and P4HA1 as the potential modulating factor to glycolysis. Besides, the expression of genes encoding glycolytic enzymes positively correlated with genes in cell cycle. InterpretationThis is the first study to identify gene expression signatures that reflect glycolysis activity, which can be easily applied to large numbers of patient samples. Our analysis establishes a computational framework for characterizing glycolysis activity using gene expression data and defines correlation of glycolysis with the hypoxia microenvironment, tumor cell cycle and proliferation at a pan-cancer landscape. The findings suggest that the mechanisms whereby hypoxia influence glycolysis are likely multifactorial. Our finding is significant not just in demonstrating definition value for glycolysis but also in providing a comprehensive molecular-level understanding of glycolysis and suggesting a framework to guide combination therapy that may block the glycolysis pathway to control tumor growth in hypoxia microenvironment.

cancer biology↗

Integrated analysis of gene correlation reveals disordered relationship between metabolism and immunity in tumor microenvironment

BackgroundMetabolism reprogramming and immune evasion are the most fundamental hallmarks for cancer survival. The complex interactions between metabolism and immune systems in tumors and their microenvironment is complicated. Researching on the correlation changes between metabolic and immune related-genes in normal and tumor tissues would help to reveal these complex interactions. MethodsIn this study, the mRNA profiles across 11 cancer types was obtained from The Cancer Genome Atlas (TCGA). Then, the spearmans correlation coefficient was calculated between metabolic and immune related-genes for each sample group. ResultsOur results showed that the number of correlated gene pairs was reduced significantly in tumor tissues compared with those of normal tissue, especially in KIRC, KIRP and STAD. Functional enrichment analysis for the universal (the pairs appeared in more than 2 cancer types) and specific (the pairs only in one specific cancer type) gene pairs across cancer types revealed top pathways which appeared in tumor and normal samples, such as phosphatidylinositol signaling system and inositol phosphate metabolism. Thereinto, the pairs in normal tissues missing in tumors may indicate they are important factors affecting immune system, such as, DGKs and PIP4ks. The correlation analysis between immune checkpoint and metabolism genes also showed a reduced correlation in tumor and had the tissue specificity, such as, FUT8 was strongly correlated with PDCD1 in the HC of STAD and they had a weaker correlation in other normal tissues and tumor types. ConclusionsOur study provides a novel strategy for investigating interaction of tumor immune and metabolism in microenvironment and offers some key points for exploring new targets including metabolic targets and immunomodulator of immune checkpoints.

bioinformatics↗

Predictions for the binding domain and potential new drug targets of 2019-nCoV

An outbreak of new SARS-like viral in Wuhan, China has been named 2019-nCoV. The current state of the epidemic is increasingly serious, and there has been the urgent necessity to develop an effective new drug. In previous studies, it was found that the conformation change in CTD1 was the region where SARS-CoV bound to human ACE2. Although there are mutations of the 2019-nCoV, the binding energy of ACE2 remains high. The surface glycoprotein of 2019-nCoV was coincident with the CTD1 region of the S-protein by comparing the I-TASSER prediction model with the actual SARS model, which suggests that 2019-nCoV may bind to the ACE2 receptor through conformational changes. Furthermore, site prediction on the surface glycoprotein of 2019-nCoV suggests some core amino acid area may be a novel drug target against 2019-nCoV.

bioinformatics↗

Single cell transcriptome of CD8+ T cells in multiple cancers reveals comprehensive exhaustion associated mechanisms

T cell exhaustion is one of the main reasons of tumor immune escape. Using single cell transcriptome data of CD8+ T cells in multiple cancers, we identified different cell types, in which Pre_exhaust and exhausted T cells participated in negative regulation of immune system process. By analyzing the co-expression network patterns and differentially expressed genes of Pre_exhaust, exhausted and effector T cells, we identified 35 genes related to T cell exhaustion, which high GSVA scores were associated with significantly poor prognosis in various cancers. In the differentially expressed genes, RGS1 showed the greatest fold change in Pre_exhaust and exhausted cells of three cancers compared with effector T cells, and high expression of RGS1 was also associated with poor prognosis in various cancers. Additionally, RGS1 protein was upregulated significantly in tumor tissues in the immunohistochemistry verification. Furthermore, RGS1 displayed positive correlation with the 35 genes, especially highly correlated with PDCD1, CTLA4, HAVCR2 and TNFRSF9 in CD8+ T cells and cancer tissues, indicating important roles of RGS1 in CD8+ T cell exhaustion. Considering the GTP-hydrolysis activity of RGS1 and significantly high mRNA and protein expression in cancer tissues, we speculated that RGS1 potentially mediate the T cell retention to lead to the persistent antigen stimulation, resulting in T cell exhaustion. In conclusion, our findings suggest that RGS1 is a new marker and promoting factor for CD8+ T cell exhaustion, and provide theoretical basis for research and immunotherapy of exhausted cells.

cancer biology↗

Integrated Sequencing & Array Comparative Genomic Hybridization in Familial Parkinson’s Disease

BackgroundParkinsons disease (PD) is a genetically heterogeneous condition; both single nucleotide variants (SNVs) and copy number variants (CNVs) are important genetic risk factors. We examined the utility of combining exome sequencing and genome-wide array-based comparative genomic hybridization (aCGH) for identification of PD genetic risk factors. MethodsWe performed exome sequencing on 110 subjects with PD and a positive family history; 99 subjects were also evaluated using genome-wide aCGH. We interrogated exome sequencing and array comparative genomic hybridization data for pathogenic SNVs and CNVs at Mendelian PD gene loci. SNVs were confirmed via Sanger sequencing. CNVs were confirmed with custom-designed high-density aCGH, droplet digital PCR, and breakpoint sequencing. ResultsUsing exome sequencing, we discovered individuals with known pathogenic single nucleotide variants in GBA (p.E365K, p.T408M, p.N409S, p.L483P) and LRRK2 (p.R1441G and p.G2019S). Two subjects were each double heterozygotes for variants in GBA and LRRK2. Based on aCGH, we additionally discovered cases with an SNCA duplication and heterozygous intragenic GBA deletion. Five additional subjects harbored both SNVs (p.N52fs, p.T240M, p.P437L, p.W453*) and likely disrupting CNVs at the PARK2 locus, consistent with compound heterozygosity. In nearly all cases, breakpoint sequencing revealed microhomology, a mutational signature consistent with CNV formation due to DNA replication errors. ConclusionsIntegrated exome sequencing and aCGH yielded a genetic diagnosis in 19.3% of our familial PD cohort. Our analyses highlight potential mechanisms for SNCA and PARK2 CNV formation, uncover multilocus pathogenic variation, and identify novel SNVs and CNVs for further investigation as potential PD risk alleles.

genetics↗

The Influence of Blood Collection Tubes in Biomarkers Screening by Mass Spectrometry

BackgroundMass spectrometry (MS) is one of the rapidly developing bio-analytical techniques in recent years and have found many biomarkers of variety of disease. Whereas pre-analytical process is one of most crucial procedure which would significantly influence the results of biomarkers screening. In the current study, we conducted a pilot analysis of serum to determine the effects of blood collection tubes in biomarkers screening.\n\nMethodsMagnetic bead separation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry were used for qualitative analysis of healthy control and serum cancer patients. A total of 24 serum samples were analyzed in this study, of which were collected from patients or healthy control using non-additive tubes or coagulant activator tubes respectively. ClinProTools were used to compare the difference among the different groups.\n\nResultsThe results demonstrated that no matter for patients or normal people, the serum protein profile changed significantly when using coagulant tubes. We also found that the effect of coagulant on serum protein of patients was smaller than that of control group. There were significant differences among 27 peaks which were obtained in the control group and the control coagulant group. However, between patient group and patient coagulant group, only 1 differential peak were obtained. Coagulant changed the protein expression difference in the original serum, and the difference expanded, narrowed even reversed, most of which are small polypeptides (Mass<3000 Da), which significantly changed the results of biomarkers screening. The results showed that 19 potential biomarkers could be found with non-additive tubes and 16 potential biomarkers could be found with coagulate activator tubes, among which only 6 were the same.\n\nConclusionsThe choice of blood collection tube significantly influence the results of biomarkers screening by MS.

cancer biology↗

Cas12a-based on-site and rapid nucleic acid detection of African swine fever

The mortality rate of hemorrhagic African swine fever (ASF), which targets domestic pigs and is caused by African swine fever virus (ASFV), can reach 100%. ASF has been reported in 25 Chinese provinces since August 2018. There is no effective treatment or vaccine for it and the present molecular diagnosis technologies have trade-offs in sensitivity, specificity, cost and speed, and none of them cater perfectly to ASF control. Thus, a technology that overcomes the need for laboratory facilities, is relatively low cost, and rapidly and sensitively detects ASFV would be highly valuable. Here, we describe an RAA-Cas12a-based system that combines recombinase-aided amplification (RAA) and CRISPR/Cas12a for ASFV detection. The fluorescence intensity readout of this system detected ASFV p72 gene levels as low as 10 aM. For on-site ASFV detection, lateral-flow strip readout was introduced for the first time in the RAA-Cas12a based system (named CORDS, Cas12a-based On-site and Rapid Detection System). We used CORDS to detect target DNA highly specifically using the lateral-flow strip readout. CORDS could identify the p72 gene at femtomolar sensitivity in an hour at 37{degrees}C, and only requires an incubator. For ease of use, the regents of CORDS was lyophilized to three tubes and remained the same sensitivity when stored at 4 {degrees}C for at least 7 days. Thus, CORDS provides a rapid, sensitive and easily operable method for ASFV on-site detection. Lyophilized CORDS can withstand long-term transportation and storage, and is ready for field applications.

molecular biology↗

The Urinary Microbiota in Relation to the Reproductive Tract Microbiota

Human urine is traditionally considered to be sterile, and whether the urine harbours distinct microbial communities has been a matter of debate. The potential link between female urine and reproductive tract microbial communities is currently not clear. Here we collected the urine samples from 147 Chinese women of reproductive age, and explored the nature of colonization by 16S rRNA gene amplicon sequencing, real-time qPCR and live bacteria culture. To demonstrate utility intra-individual Spearmans correlation was used to explore the relationship between urine and multi-sites of the reproductive tract. PERMANOVA was also performed to explore potential correlations between the lifestyle and various clinical factors and urinary bacterial communities. Our data demonstrated distinct bacterial communities in urine, indicative of a non-sterile environment. Types of diverse, Streptococcus-dominated, and Lactobacillus-dominated were the three most common types in the cohort. Detailed comparison of the urinary microbiota to the multi-sites of reproductive tract microbiota demonstrated the urinary microbiota was more similar to the microbiota in the cervix and uterine cavity instead of vagina in the same women. Our data demonstrates the potential connectivity of the microbiota in the female urogenital system and provided insight into the exploration of urethra and genital tract diseases.

microbiology↗

ELIMINATION OF EGFR-OVEREXPRESSING CANCER CELLS BY CD32 CHIMERIC RECEPTOR T CELLS IN COMBINATION WITH CETUXIMAB OR PANITUMUMAB

Cetuximab and panitumumab bind the human epidermal growth factor receptor (EGFR). While the chimeric cetuximab (IgG1) triggers antibody-dependent-cellular-cytotoxicity (ADCC) of EGFR positive target cells, panitumumab (a human IgG2) does not. The inability of panitumumab to trigger ADCC reflects a poor binding affinity of human IgG2 Fc for the Fc{gamma}RIII (CD16) on NK cells. However, both human IgG1 and IgG2 bind the Fc{gamma}RII (CD32) to a similar extent. Here, we have compared the ability of T cells, engineered with a novel low-affinity CD32131R -chimeric receptor (CR), and those engineered with the low-affinity CD16158F-CR T cells in eliminating EGFR positive epithelial cancer cells (ECCs) in combination with cetuximab or panitumumab. Following T cell transduction, the percentage of CD32131R-CR T cells was (74{+/-}10) significantly higher than that of CD16158F-CR T cells (46{+/-}15). Only CD32131R-CR T cells bound panitumumab. CD32131R-CR T cells combined with the mAb 8.26 (anti-CD32) and CD16158F-CR T cells combined with the mAb 3g8 (anti-CD16) eliminated colorectal carcinoma (CRC), HCT116Fc{gamma}R+ cells, in a reverse ADCC assay in vitro. Cross-linking of CD32131R-CR on T cells by cetuximab or panitumumab and CD16158F-CR T cells by cetuximab induced elimination of triple negative breast cancer (TNBC) MDA-MB-468 cells, and secretion of IFN gamma (IFN{gamma}) and tumor necrosis factor alpha (TNF). Neither cetuximab nor panitumumab induced Fc{gamma}-CR T anti-tumor activity against KRAS-mutated HCT116, non-small-cell-lung-cancer, A549 and TNBC, MDA-MB-231 cells. ADCC of Fc{gamma}-CR T cells was significantly associated with the over-expression of EGFR on ECCs. In conclusion, CD32131R-CR T cells are efficiently redirected by cetuximab or panitumumab against BC cells overexpressing EGFR.\n\nArticle categoryTumor Immunology and Microenvironment\n\nNovelty and ImpactMonoclonal antibody-redirected Fc{gamma}-CR T cell immunotherapy represents a promising approach in the fight against cancer. Here, we expand the application of this methodology to TNBC overexpressing the EGFR utilizing a novel CD32A131R-CR in combination with anti-EGFR mAbs. Our study supports the use of CD32A131R-CR T cells combined with panitumumab or cetuximab for targeting TNBC cells overexpressing the EGFR. Our results may be utilized as a platform for the rational design of therapies targeting TNBC overexpressing EGFR.

immunology↗

The transferability of lipid-associated loci across African, Asian and European cohorts

The under-representation of non-European samples in genome-wide association studies could ultimately restrict who benefits from medical advances through genomic science. Our aim was therefore to address the fundamental question whether causal variants for blood lipids are shared across populations.\n\nA polygenic score based on established LDL-cholesterol-associated loci from European discovery samples had consistent effects on serum levels in samples from the UK, Uganda and Greek population isolates (correlation coefficient r=0.23 to 0.28 per LDL standard deviation, p<1.9x10-14). Trans-ethnic genetic correlations between European ancestry, Chinese and Japanese cohorts did not differ significantly from 1 for HDL, LDL and triglycerides. In each study, >60% of major lipid loci displayed evidence of replication with one exception. There was evidence for an effect on serum levels in the Ugandan samples for only 10% of major triglyceride loci. The PRS was only weakly associated in this group (r=0.06, SE=0.013). We establish trans-ethnic colocalization as a method to distinguish shared from population-specific trait loci.\n\nOur results provide evidence for high levels of consistency of genetic associations for cholesterol biomarkers across populations. However, we also demonstrate that the degree of shared causal genetic architecture can be population-, trait- and locus-specific. Efforts to implement genetic risk prediction in clinical settings should account for this.

genetics↗

FRACTIONAL DELETION OF COMPOUND KUSHEN INJECTION, A NATURAL COMPOUND MIXTURE, INDICATES CYTOKINE SIGNALING PATHWAYS ARE CRITICAL FOR ITS PERTURBATION OF THE CELL CYCLE.

We have used computational and experimental biology approaches to identify candidate mechanisms of action of a traditional Chinese medicine. Compound Kushen Injection (CKI), in a breast cancer cell line in which CKI causes apoptosis. Because CKI is a complex mixture of plant secondary metabolites, we used a high-performance liquid chromatography (HPLC) fractionation and reconstitution approach to define chemical fractions required for CKI to induce apoptosis in MDA-MB-231 cells. Our initial fractionation separated major from minor compounds, and showed that the major compounds accounted for little of the activity of CKI. By systematically perturbing the major compounds in CKI we found that removal of no single major compound could alter the effect of CKI on cell viability and apoptosis. However, simultaneous removal of two major compounds identified oxymatrine and oxysophocarpine as critical compounds with respect to CKI activity. We then used RNA sequencing and transcriptome analysis to correlate compound removal with gene expression and phenotype data. We determined that many compounds in CKI are required for its effectiveness in triggering apoptosis but that significant modulation of its activity is conferred by a small number of compounds. In conclusion, CKI may be typical of many plant based extracts that contain many compounds in that no single compound is responsible for all of the bioactivity of the mixture and that many compounds interact in a complex fashion to influence a network containing many targets.

pharmacology and toxicology↗

The LIM-Only Protein FHL2 is Involved in Autophagy to Regulate the Development of Skeletal Muscle

Four and a half LIM domain protein 2 (FHL2) is a LIM domain protein expressed in muscle tissue whose deletion is causative of myopathies. Although FHL2 has a confirmed important role in muscle development, its autophagy-related function in muscle differentiation has not been fully determined. To explore the role of FHL2 in autophagy-related muscle regulation, FHL2-silenced and -overexpressing C2C12 mouse cells were examined. Immunofluorescence and co-immunoprecipitation assay findings showed that FHL2 silencing reduced LC3- protein expression and the amount of LC3 that co-immunoprecipitated with FHL2, indicating that FHL2 interacts with LC3- in the formation of autophagosomes. Moreover, the expression of muscle development marker genes such as MyoD1 and MyoG was lower in FHL2-silenced C2C12 cells but not in FHL2-overexpressing C2C12 cells. Electron microscopy analysis revealed large empty autophagosomes in FHL2-silenced myoblasts, while flow cytometry suggested that FHL2 silencing made cells more vulnerable to staurosporine-induced cell death. In conclusion, we propose that FHL2 interacts with LC3- in autophagosome formation to regulate the development of muscle cells.

molecular biology↗

Roles of Polycomb gene EED in pathogenesis and prognosis of acute myeloid leukemia and diffuse large B cell lymphoma

In this study, we performed correlation analysis of polycomb gene EED and hematologic malignancies using the omics and clinical data of acute myeloid leukemia (LAML) and diffuse large B-Cell lymphoma (DLBC) from TCGA database. We found that: (1) High EED mRNA level was associated with poor prognosis and high CALGB cytogenetics risk of LAML patients. (2) EED mRNA level in DLBC cancer cells was higher than control cells. (3) EED gene expression could be regulated by both copy number alterations and DNA methylation. (4) Additionally, there were different EED co-expression genes nets in the two kinds of hematologic malignancies. In all, we confirmed that there are potential clinical significance of EED gene in pathogenesis and prognosis of hematologic malignancies.

systems biology↗